As others have said, no. However, often patches that don't require a reboot have files that are busy when the patch is installed. You will see a message concerning such and that they are renamed (I think) and added to a list to be cleaned up at the next reboot. If so, I don't like to wait too long before scheduling a reboot. Maybe it doesn't matter but I feel better.
And as Bill says, you may need to stop a particular product before patching it. You should always read the patch text file.
Darrell
"What, Me Worry?" - Alfred E. Neuman (Mad Magazine)